dl and fortran

[John W. Eaton]

On 18-Jun-1997, Stef Pillaert BK <address@hidden> wrote:

| I would like to use the LAPACK-function DSYSVX to solve symmetric (but not
| positive definite) matrices.
| 
| Right now, I'm saving my matrices to a file, I call a fortran
| program, where I call DSYSVX, I save
| the results to files, and read the results in octave.
| 
| I would prefer to do all this with dynamic linking, but since I'm not a
| c++-specialist (neither fortran...), I have a few little problems:
| 
| * dynamic linking works (well, not in 2.0.7, but I should wait for 2.0.8,
| am I well informed?). But I have no idea how to call my fortran-program 
| from within a file like "oregonator.cc" (see examples). 

You don't say what kind of system you are using, but dynamic linking
should work on most systems with all 2.0.x releases.  There are some
very minor problems with dynamic linking on HP systems in 2.0.7, but I
think patches have been posted to the bug-octave mailing list.  You
can find a pointer to the archive of bug-octave messages on Octave's
web page (http://www.che.wisc.edu/octave).  There were also some
problems with the mkoctfile script, but believe I posted a fixed
version of that as well.

| * How about precision? Does octave use "double precision"-equivalent (I'm
| talking Fortran now...) And how do I pass variables\values?

Yes, numeric values in Octave are double precision.

| Is it possible to give me a small example how to do all this?

There are lots of examples distributed with Octave.  The file
example/hello.cc includes a list of other functions that you can use
as examples.

jwe